I've just been pondering doing a few little things with my cb400n as the exhaust is nearly rusted through in the collector.
I'm thinking of making a new exhaust for it as most systems run to nearly the value of the bike and i'm handy with a welder and grinder anyway. If i remove the the collector and run straight pipes will it affect power and ridability or am I just better off running a h pipe across to balance the pipes. Will changing the pipe result in the need for upping the jet sizing or should i get away with it. And lastly can anyone let me know where the best place to get carby jets and shorty mufflers from (the ones that look like car hotdog mufflers)

H box, or X pipes, are more balanced. I'm sure Mr Honda spent thousands of Yen in R + D, perfecting the exhaust.
If you go for straight pipes, go up a size in jets. A free flowing exhaust "may" lead to a lean mixture, and a doughnut shaped piston. . because of reduced back pressure.

yeah i know mr honda did quite a good job with the exhaust system but he didnt expect the bike to sit out in the rain for years, and I got quotes for a new system and it runs too $100 less than i paid for the bike. Thanks for the advice

f it just build what ya want an suck it from there it will still run ya just make it run better. loud pipes save lives thats what they say .open em up make em scream forget the harley mufflers they were no good on them they ll be no good for you ya might have to drill some jets a bit bigger but you will sort it . piece of cake go for it ya like every one else we deserve it,hook in cheers

IM NOT CRAZY ITS JUST OTHER PEOPLES PERCEPTION OF MY NORMALITY THAT DIFFERS